Message 207703 - Python tracker

I'll take a stab at this one, but I may make you rue the day you said you'd review until your eyes bleed ;)

Here's a partial patch to PC/winreg.c, converting only the CloseKey function just to make sure I have some basic idea of what I'm doing.

(Also, if anyone else wants this one, please don't hesitate on account of me; just let me know and it's yours.)